package thread.pool.core.util;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.reflect.TypeToken;

import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;

public class GsonTool {
    private static final Gson gson;

    static {
        gson = (new GsonBuilder()).setDateFormat("yyyy-MM-dd HH:mm:ss").create();
    }

    public GsonTool() {
    }

    public static String toJson(Object src) {
        return gson.toJson(src);
    }

    public static <T> T fromJson(String json, Class<T> classOfT) {
        return gson.fromJson(json, classOfT);
    }

    public static <T> T fromJson(String json, Class<T> classOfT, Class<?> argClassOfT) {
        Type type = new GsonTool.ParameterizedType4ReturnT(classOfT, new Class[]{argClassOfT});
        return gson.fromJson(json, type);
    }

    public static <T> List<T> fromJsonList(String json, Class<T> classOfT) {
        return gson.fromJson(json, (new TypeToken<List<T>>() {
        }).getType());
    }



    public static class ParameterizedType4ReturnT implements ParameterizedType {
        private final Class<?> raw;
        private final Type[] args;

        public ParameterizedType4ReturnT(Class<?> raw, Type[] args) {
            this.raw = raw;
            this.args = args != null ? args : new Type[0];
        }

        public Type[] getActualTypeArguments() {
            return this.args;
        }

        public Type getRawType() {
            return this.raw;
        }

        public Type getOwnerType() {
            return null;
        }
    }
}
